Electrophotographic apparatus



June 9, 1964 1. M. SAGE ETAL 3,136,233

ELECTROPHOTOGRAPHIC APPARATUS Filed June 2'7, 1960 2 Sheets-Sheet 1 INVENTORS IRA M SAGE d BERNARD KAMINSTEIN ATTORNEY FIG.5

June 9, 1964 l. M. SAGE ETAL 3,136,233

ELECTROPHOTOGRAPHIC APPARATUS Filed June 27, 1960 I 2 Sheets-Sheet 2 F|G.4 H53 A 5 INVENTORS 4/5 IRA M SAGE 4/1 BERNARD KAMINSTEIN 4M ATTORNEY United States Patent 3,136,233 ELECTROPHOTOGRAPHIC APPARATUS Ira M. Sage, North Bergen, and Bernard Kaminstein, Paramus, N.J., assignors to Keuliel & Esser Company, Hoboken, N.J., a corporation of New Jersey Filed June 27, 1960, Ser. No. 38,865 Claims. (Cl. 95-137) The present invention relates to making prints or copies of documents and more particularly relates to electrostatic sensitizing of a photoconductive surface projecting an image on the photoconductive surface and developing the image with a toner applied and fixed after the projection of the image. Heretofore, it has been known to provide apparatus for producing electrostatic images, but the previously known equipment has not been entirely satisfactory, due to the difiiculty of placing the copy paper in position and retaining it without regard to the specific size thereof, and the equipment has been complicated to manufacture and difficult to operate.

An object of the present invention is to provide a printer which can be operated by relatively unskilled persons and can be used to reproduce drawings, documents and images of sizes commonly used for drawings and the like.

Another object is to provide equipment which is housed in a neat appearing housing and which can be readily loaded with the master to be duplicated and with'the copy paper on which the image is to be projected.

A still further object is to provide a projection copy apparatus for making copies from masters of small sizes.

Other objects and advantages will be apparent as the description proceeds and upon reference to the accompanying drawings, wherein:

FIG. 1 is a perspective of the cabinet type unit outlined in dot-dash lines and showing the projector in dotdash lines with the path of projection of the image being shown to include a mirror and a copy material receiving platen, the platen being located at the top of the box for ease of loading and the platen being rotatable to position the copy material facing the cabinet interior.

FIG. 2 is a transverse section taken substantially on line 2-2 of FIG. 1, showing the toner applying magazine and the belt with the magnets thereon and also showing the rail mounting for rectilinear movement of the magazine.

FIG. 3 is a fragmentary longitudinal section with parts omitted and parts broken away taken substantially on line 3-3 of FIG. 2, showing the roller support for maintaining rectilinear movement of the carriage for the toner magazine and fuser and the carriage for the separately movable electrostatic charging bar.

FIG. 4 is a fragmentary horizontal section with parts broken away taken substantially on line 4-4 of FIG. 2, showing the pulley drive for moving the toner-carrying belts in opposite directions.

FIG. 5, is a horizontal section taken substantially on line 5-5 of FIG. 1, showing the mounting of the tension maintaining idler pulleys for the toner-applying belts.

FIG. 6 is a fragmentary vertical section taken substantially on line 6-6 of FIG. 1 through an end of the platen and the adjacent portion of the top of the unit showing the latch for selectively retaining the platen in copy paper receiving and removal position shown or in copy charging, exposing, developing and fixing position.

FIG. 7 is a vertical section through a side edge of the platen and the adjacent portion of the top of the unit, showing the angular arrangement for receiving the side edge of the copy material for initially holding the copy material in place. p

Briefly, the present application comprises a cabinet hav- 3,136,233 Patented June 9, 1964 ing an opening in its top with a movably mounted platen positioned to close said opening and mounted so that a copy-bearing surface thereof may face outwardly in copy bearer receiving or removal position or may face inwardly for sensitizing, image receiving and developing. A projector is mounted on the cabinet and a mirror is mounted in line withthe projector for reflecting an image from the projector onto the copy-bearer on the surface of the platen when said copy bearing surface faces the interior of the cabinet thereby providing for exposing an image on the copy bearer on the platen.

A first carriage having a corona discharge bar thereon is mounted in the cabinet for'rectilinear movement adjacent the platen for applying an electrostatic charge to the copy bearer'with the normal inoperative position of the charging bar carriage lying beyond the platen. After the surface of the copy bearer is electrostatically charged, an image is projected onto the copy bearer and thereafter a second carriage movably mounted on the same rails as the first carriage but normally located at the opposite end of the cabinet is moved along the charged and image exposed surface of the copy bearer carrying developer into the electrostatic range of the latent image to produce a visible image. Such carriage also supports a fixing device in the form of a heater which heater is normally inoperative in the first movement of the second carriage, but on the return movement of the second carriage the heater is operated to cause the developer to adhere to the copy bearer by a fusing action whereby the copy is'completed when the second carrier returns to its normal inoperative position.

Referring more specifically to FIGS. 1 to 3 of the drawings, a framework support is provided by suitable structural members (not shown) to which side panels 10L, ltlR, end panels 11, 11B and a top panel 12 are applied, thereby providing an enclosure. The top panel 12 is provided with a platen receiving opening 13 in its central portion and a copy receiving platen 14 provided with a hollow axle shaft sections 15L, 15R rotatably mounted in bearings 16L, 16R on theframework, with the platen being held in horizontal position by a detent 17 mounted on the top 12 and having a spring pressed ball selective engageable with a depression 18 in each end of the platen whereby the platen may be retained in copy paper receiving and removing position with the grooves 19 and 20 upwardly as shown in FIGS. 1 and 6 or the platen may be rotated with the grooved copy paper receiving surface facing the interior of the cabinet in image receiving position. The outer and inner grooves 19 and 20 (FIGS. 1 and 7) of the platen provide spaces for applying vacuum through hollow axle 15 and suction lines to spaced portions along the grooves 19 and 20 for retaining the copy paper in position by'vacuum.

One end of the hollow shaft 15L communicates only with the outer groove 19 at a plurality of points along the groove 19 and a valve controlled suction tube 19A communicates therewith while a second valve controlled suction tube 20A communicates through the other end of axle 51R only with the inner groove 20 at a plurality of points along the groove 20. The grooves provide for vacuum retention of the copy paper in position on the platen. The vacuum can be applied to a single grooveat a time by the proper actuation of the valves connected to a "acuum source. The grooved side edge portions of the platen 14 are chamfered, and elongated obtuse angle members 21 are secured to the edges by one flange with the other flange and the chamfer 22 to receive the copy paper and assist in guiding the copy paper into position for retention on the platen by the vacuum produced in grooves 19 and 20. The free flange extends beyond the copy receiving surface of the platen to assist in locating the copy paper.

A projector 23 shown in phantom outline (FIG. 1) is adjustably mounted on the cabinet to project an image from a microfilm or the like into the cabinet and onto a mirror 24 arranged in angular relation and then onto the platen 14. Cross members 25 support a mirror backing 26 supporting the mirror 24, the backing being adjustably secured to members 25 by slotted brackets 26A through which screws 26B pass to clamp the mirror support and mirror so that the angularity of the mirror with relation to the hne of projection can be accurately adjusted to produce an accurately focused image on the copy paper carried by the platen when the platen is positioned with the grooved paper supporting side thereof facing inwardly of the cabinet.

It will be apparent that both surfaces of the platen can be arranged to take a copy bearer so a copy bearer can be applied on one surface of the platen while the copy is being made on the other surface.

Referring to FIGS. 1 and 2, supported on the framework is a first rail 27 of circular section and a channel shaped second rail 28 on the other side with the channel opening toward said first rail. A first carriage 29 includes a pair of end members 29L, 29R rigidly connected by a cross member 30. End member 29R has a G-shaped sleeve 31 secured by its intermediate portion to the end plate 29R with the sleeve embracing the first rail 27. A first C-shaped roller assembly 32 having a rabbet formed in the periphery of its body has the rabbet received in the adjacent forward end of the C-shaped sleeve while C-shaped roller assembly 32B is supported in the rear end of sleeve 31 thereby providing a positive guide for rectilinear movement. Each C-shaped roller assembly is provided with upper rollers 33L, 33R and a lower roller 34 for engagement with the rail 27 and the two C-shaped roller assemblies on sleeve 31 fixed to carriage 29 assure rectilinear movement of the first carriage 29. The opposite end 29L of the carriage 29 is provided with one or more guide rollers 35 received in the channel 28 thereby providing for complete support of the carriage 29 for rectilinear movement from adjacent the back wall 11B to adjacent the front wall 11 of the cabinet. The rail 27 can be supported by intermediate its ends by legs 27A which extend to the framework to rigidity the rail.

On the carriage 29 corona discharge electrode wires 36 are supported in suitable insulators and are connected to a lead which hangs down into the cabinet and does not interfere with the movement of the carriages 29 or 41 and does not extend into the path of projection during projection. To move the carriage 29 a motor 37 drives a gear reduction unit 38 which drives a capstan type roller 39 around which a cable 40 is wound for at least one turn with such cable 40 extending from the front wall 11 to the back wall 11B of the cabinet for support thereby. Upon operating the motor 37 the capstan type roller 39 rotates causing the carriage 29 to move rectilinearly and by suitably reversing the motor at the proper time the carriage 29 is moved in the opposite direction, suitable limit switches and reversing switches are provided for limiting the movement and controlling the direction thereof.

A second carriage 41 having end plates 41L, 41R maintained by screw attachment in accurate space relation in the carriage 41 by the triangular shaped toner receiving magazine, such magazine includes the generally triang'ular front and back plates 42, 42A with inclined bottoms 43, 43 which are spaced apart at their bottom ends thereby providing an opening for removal of the contents of the toner magazine. Such opening is closed by a resilient sheet of gasket material 43A of sponge rubber or the like supported on a door 43B hingedly mounted at the forward end to a bracket 43C and retained in closed position by a latch 43D, the magazine being open at its top, except for shields 43E preventing loss of toner. The second carriage 41 is mounted for rectilinear movement by a =C-shaped sleeve 31A and roller assemblies which are identified in the same manner and with the same reference used in the description of carriage 29 with the suffix A added to the reference numeral, and the carriage 41 is moved by means of a motor 37A and a capstan type roller 39A with the supply of current carried by supply lines which hang down from the carriage in a manner to avoid interference with the projection of light and the carriage movements.

A belt supporting shelf 44 is removably mounted adjacent the open top of the toner magazine with its upper surface substantially tangent with the belt pulleys 45, 46, 47 and 48, which pulleys are mounted on shafts 49L and 49R which shafts are rotatably mounted in bearings supported in plates 41A, 41B fixed to corresponding end plates 41L and MR. A pair of idler pulleys 50 and 51 are adjustably mounted in the lower apex portion of the triangular shaped toner magazine and the pulleys 46, 48 and 51 carry a first belt 52 while pulleys 45, 47 and 50 carry a second belt 53. Each belt has fixedly mounted thereon a plurality of magnets 54 secured to the belt in any suitable manner as by rivets or the like, the belt being of nonmagnetic material. I

The belts 52 and 53 are driven in opposite directions from a single motor 55 having a pair of pulleys thereon with the inner pulley shown as being connected by a V-belt 41LB to driven pulley 49LA and the outer pulley being connected by a crossed belt 49RB to a V-belt pulley 49RA thereby producing opposite rotation of shafts 49L and 4%R from a single direction of rotation of motor 55.

It will be note (FIG. 4) that the shafts 49L and 49R are rotatably mounted in suitable ariti=friction bearings in the toner magazine and shaft 49L fixedly car'r'ied toner belt driving pulley 45 and also freely rotatably carries idler pulley 46 so that rotation of shaft 49L produces a driving rotation of pulley 45 and thereby of toner belt 53 while shaft 49L has substantially no effect on pulley 46 and belt 52. However, shaft 49R has a pulley 48 fixed thereto whereby rotation of shaft 49R causes movement of toner belt 52 while pulley 47 is freely rotatable on shaft 49R for a guiding action on belt 53. Therefore, operation of motor 45 causes opposite movement of toner belts 52 and 53 and of the magnets 54 carried thereby. To maintain the belt taut, the idler pulleys 51 and 52 are removably mounted, the pulleys 52 being freely rotatably mounted on an externally shouldered internally threaded sleeve 50A. The inner race of a ballbearing assembly SilC is mounted on the sleeve 50A and being clamped be tween the flange of said sleeve and an externally telescop' ing spacer, sleeve 59D which engages against the inner surface of plate 42, the outer surface of such plate being engaged by a large washer 50E which is held in place by a machine screw 50B passing through an elongated slot 50F providing for limited vertical adjustment and held in position by the head of machine screw engaging a large washer 50E effectively covering the elongated opening 50F, and providing for the clamping action. The outer race of bearing 53C is received in a counterbore in the pulley 50 and is retained therein by a split ring 506 re ceived in a groove, thereby providing for complete accurate mounting of the idler pulley 50 to obtain snug adjustment of the toner belt 53 cooperating therewith. The pulley 51 is similarly mounted in the back wall 42A of the toner magazine.

The belts 52 and 53 have their upper runs pass over the shelf guide plate 44 and by moving in opposite directions carry toner in brushes on the magnets, which brushes of toner engage the surface of the copy material carried by the grooved surface of the platen 14 without requiring mechanical contact of the applying means or magnets with the copy bearer. The guide shelf 44 is provided with a plurality of apertures 44A between the belts adjacent the ends of the shelf for the discharge of excess toner material which may fall from the magnets to avoid piling up of excess toner on the shelf.

The toner used is of the magnetic carrier type having magnetizable carrier particles and smaller sized particles of thermoplastic toner material, and during use the thermoplastic toner particles are used up. Toner material is added to make up for the toner which has been used and when it is desired to clean out the magazine the door 43D at the bottom of the magazine is opened and a suitable receptacle placed thereunder. The door 43D also serves to facilitate manipulating the belt and the idler pulleys.

Secured to the carriage 41 is a heater unit comprising a trough-shaped housing 56 in which a plurality of re sistance heating wires 57 are located and such resistance wires are heated by the passage of electricity for producing suflicient heat after application of the toner to the electrostatic laten image to fuse the toner to the copy bearer, the trough-shaped housing 56 being secured to the carriage 41 by brackets 58. The wires 57 are secured to separately insulated E-shaped terminals at one end of the trough 56 and pass over insulators at the other end so each wire is twice the length of the trough.

To illustrate an example of the operation of the printer, the attendant places a sheet of zinc oxide coated paper on the grooved surface of the platen 14 by causing the side edges of the paper to engage the free flanges of angle member 41 so that such edges are guided into the slot between the free flanges and the chamfer 22. A vacuum is applied by opening the valves from a vacuum source to the suction lines 19A and 20A producing suction along the grooves 19 and 20, thereby causing the paper to be retained in flat contact with the platen 14. Where a small size sheet is to be used the sheet is placed on the platen to cover groove 20 and vacuum is applied by operation of the valve to line 20A. The platen is rotated by means of the hand wheel 15C or by contact with the platen by hand or otherwise, thereby causing the copy bearer to face into the cabinet the operative position of the platen being maintained by detent 17. A switch is then closed to energize the corona discharge electrode 36 and to operate motor 37, causing the carriage 29 with the charging bar to move closely adjacent the copy bearer in a movement toward the projector end of the cabinet and to return, suitable limit and reversing switches being provided for the purpose. Thereafter, an image is projected on a microfilm or the like from projector 23 against mirror 24 and onto the copy bearer, thereby causing discharge of the electrostatic charge on the copy bearer in the region where light has been projected and in proportion to the intensity of the light. Thereafter a switch is closed to operate motor 37A, causing carriage 41 to move away from projector 23 and substantially simultaneously therewith a switch is closed to operate motor 55, which causes movement of belts 52 and 53 carrying toner in brushes formed at each magnet 54, and as the carriage 41 is moved rectilinearly the brushes of magnetizable carrier and toner engage and brush the latent image surface of the copy bearer. The toner is retained by the electrostatic attraction of the copy bearer, and after movement of the carriage 41 to the back end of the platen 14 the carriage is returned by suitable operation of limit and reversing switches. The heating resistance wires 57 are energized when carriage 41 is adjacent the back 11B and upon return movement the image is fixed by the fusing action resulting from the heating of the toner by the heating resistance wires 57. After the return of carriage 41 to the front the platen is rotated to bring the copy bearer or copy paper on the outer surface of the cabinet, providing for removal of the completed copy and insertion of another copy bearer.

It will be apparent that various changes may be made within the spirit of the invention as defined by the valid scope of the appended claims.

What is claimed is:

1. A reproduction unit comprising a housing of generally rectangular shape, including a framework with plates closing the sides, end and top of the housing, means to mount a projector on one end of the housing, a mirror disposed in the path of the projector for directing an image toward the top of the housing, the top plate of said housing being provided with a platen receiving opening, a platen in said opening for substantially completely closing such opening, means to support said platen for pivotal movement about an axis in the plane of said platen with said axis rotatably mounted in said housing, a circular rod substantially parallel with one side of the housing and extending from one end to the other, a channel mounted adjacent the other side of the housing and extending from one end to the other, a first carriage mounted on said rod and said channel for rectilinear movement from one end of the housing to the other, a charging bar including corona discharge electrode means on said first carriage for charging a surface on the platen as the carriage moves adjacent the surface, a second carriage, means to movably mount said second carriage on said rod and channel for movement between one end and the other of said cabinet, said second carriage including a developer magazine, a pair of pulleys at spaced positions of the developer magazine, a pair of developer carrying belts mounted on said pulleys, a motor mounted on said second carriage for rotating at least some of said pulleys for causing one belt to move in one direction from one side to the other and the other belt to move in the opposite direction, a heater mounted on said second carriage on the end thereof adjacent the first carriage, means to move each of said carriages the length of said platen, means to operate said corona discharge electrode, said heater, and said motor for moving said belts in sequence, whereby said charging bar passes the length of said platen and returns, and said second carriage passes the length of said platen and returns while said belts are moving, said heater being energized on the return movement of said second carriage, means for retaining a sheet of copy material on one surface of said platen whereby said sheet of copy material on said one surface of said platen may face out of the cabinet for reception and removal of a sheet of copy material and thereafter said platen can be rotated so that said copy material faces inside the cabinet for charging, exposing, developing and fixing.

2. The invention according to claim 1 in which the platen is pivotally mounted on an axis between the inoperative positions of said carriages and each carriage is provided with a motor and a capstan type roller driven thereby, and a cable is secured to the housing beyond the operative positions of the carriages and engages the cap stan type rollers. I

3. The invention according to claim 1 in which the platen is provided with a groove adjacent its periphery and a groove adjacent its central portion, means to apply suctionto said grooves selectively whereby large or small sheets may be retained on said platen in both copyreceiving and exposing positions.

4. The invention according to claim 1 in which the side edges of said platen are provided with obtuse angle members with one flange of the angle member projecting above the copy-receiving surface of the platen to provide for ease of positioning and retention of the side edge portions of the copy adjacent the outside groove.

5. A unit for reproduction of copies comprising a housing, said housing being provided with a platen receiving opening in the top thereof, a copy bearer supporting platen in said opening for substantially completely closing such opening, means tosupport said platen for movement so one surface of said platen selectively faces downwardly into and upwardly out of said housing, means to support a copy bearer on'said one surface, a first carriage mounted in said housing for movement across said opening, means on said first carriage for charging a copy bearer on said one surface on said platen, means to direct an image on the charged copy bearer, a second carriage mounted for movement across said opening, a developer magazine mounted on said second carriage,

7 means to apply developer from said magazine to the copy bearer when the copy bearer faces downwardly, fixing means movably mounted in said housing to cause the developer to be fixed to the copy bearer, and means to operate said aforementioned means in sequence to make 5 a copy.

References Cited in the file of this patent UNITED STATES PATENTS 2,221,776 Carlson Nov. 19, 1940 5: Hayford Apr. 7, 1959 Mayo et a1 June 30, 1959 Stravrakis et a1. Nov. 3, 1959 Limberger Aug. 30, 1960 Giaimo May 16, 1961 Crumrine et a1 Nov. 21, 1961 Bliss June 26, 1962 Limberger Mar. 19, 1963 Keller et a1. Apr. 2, 1963 

1. A REPRODUCTION UNIT COMPRISING A HOUSING OF GENERALLY RECTANGULAR SHAPE, INCLUDING A FRAMEWORK WITH PLATES CLOSING THE SIDES, END AND TOP OF THE HOUSING, MEANS TO MOUNT A PROJECTOR ON ONE END OF THE HOUSING, A MIRROR DISPOSED IN THE PATH OF THE PROJECTOR FOR DIRECTING AN IMAGE TOWARD THE TOP OF THE HOUSING, THE TOP PLATE OF SAID HOUSING BEING PROVIDED WITH A PLATEN RECEIVING OPENING, A PLATEN IN SAID OPENING FOR SUBSTANTIALLY COMPLETELY CLOSING SUCH OPENING, MEANS TO SUPPORT SAID PLATEN FOR PIVOTAL MOVEMENT ABOUT AN AXIS IN THE PLANE OF SAID PLATEN WITH SAID AXIS ROTATABLY MOUNTED IN SAID HOUSING, A CIRCULAR ROD SUBSTANTIALLY PARALLEL WITH ONE SIDE OF THE HOUSING AND EXTENDING FROM ONE END TO THE OTHER, A CHANNEL MOUNTED ADJACENT THE OTHER SIDE OF THE HOUSING AND EXTENDING FROM ONE END TO THE OTHER, A FIRST CARRIAGE MOUNTED ON SAID ROD AND SAID CHANNEL FOR RECTILINEAR MOVEMENT FROM ONE END OF THE HOUSING TO THE OTHER, A CHARGING BAR INCLUDING CORONA DISCHARGE ELECTRODE MEANS ON SAID FIRST CARRIAGE FOR CHARGING A SURFACE ON THE PLATEN AS THE CARRIAGE MOVES ADJACENT THE SURFACE, A SECOND CARRIAGE, MEANS TO MOVABLY MOUNT SAID SECOND CARRIAGE ON SAID ROD AND CHANNEL FOR MOVEMENT BETWEEN ONE END AND THE OTHER OF SAID CABINET, SAID SECOND CARRIAGE INCLUDING A DEVELOPER MAGAZINE, A PAIR OF PULLEYS AT SPACED POSITIONS OF THE DEVELOPER MAGAZINE, A PAIR OF DEVELOPER CARRYING BELTS MOUNTED ON SAID PULLEYS, A MOTOR MOUNTED ON SAID SECOND CARRIAGE FOR ROTATING AT LEAST SOME OF SAID PULLEYS FOR CAUSING ONE BELT TO MOVE IN ONE DIRECTION FROM ONE SIDE TO THE OTHER AND THE OTHER BELT TO MOVE IN THE OPPOSITE DIRECTION, A HEATER MOUNTED ON SAID SECOND CARRIAGE ON THE END THEREOF ADJACENT THE FIRST CARRIAGE, MEANS TO MOVE EACH OF SAID CARRIAGES THE LENGTH OF SAID PLATEN, MEANS TO OPERATE SAID CORONA DISCHARGE ELECTRODE, SAID HEATER, AND SAID MOTOR FOR MOVING SAID BELTS IN SEQUENCE, WHEREBY SAID CHARGING BAR PASSES THE LENGTH OF SAID PLATEN AND RETURNS, AND SAID SECOND CARRIAGE PASSES THE LENGTH OF SAID PLATEN AND RETURNS WHILE SAID BELTS ARE MOVING, SAID HEATER BEING ENERGIZED ON THE RETURN MOVEMENT OF SAID SECOND CARRIAGE, MEANS FOR RETAINING A SHEET OF COPY MATERIAL ON ONE SURFACE OF SAID PLATEN WHEREBY SAID SHEET OF COPY MATERIAL ON SAID ONE SURFACE OF SAID PLATEN MAY FACE OUT OF THE CABINET FOR RECEPTION AND REMOVAL OF A SHEET OF COPY MATERIAL AND THEREAFTER SAID PLATEN CAN BE ROTATED SO THAT SAID COPY MATERIAL FACES INSIDE THE CABINET FOR CHARGING, EXPOSING, DEVELOPING AND FIXING. 